Martelli disclosed an "Assemblable and Stackable Crate of Plastic Material and Apparatus for Assembling Same" in his European Patent Application of Application No. 82107044.8 filed on Aug. 4, 1982, in which the crate consists of bottom (F) and of sidewalls (p1, P2) which in a second operative step are secured in their erected position of use to the bottom (F). Between each one of the sidewall (P1, P2) and the bottom (F) there are provided articulated connection means (1, 3, 4, 5, 6, L) which permit to raise the sidewalls (P1, P2), initially coplanar to the crate bottom (F), in order to form the crate by an angular movement through about 90.degree. (The copy of Martelli's application is enclosed herewith for the examination reference). However, Martelli's crate has the following defects:
1. For knocking down the sidewalls from the bottom or erecting the sidewalls on the bottom, all the connecting points must be manually disassembled or assembled to cause inconveniences for the user. PA0 2. All the connecting extensions, with their corresponding sockets, must be carefully fabricated or processed to increase production complexibly for their mutual smooth engagement or disengagement, since the engagement/disengagement is an angular movement other than the normal linear movement.
The present inventor has found the defects of such an European patent application, and invented the present gravitationally-operating collapsible basket.